Lamp capping machine



A g- 2 1967 F. w. JEFFERIES LAMP CAPPING MACHINE 3 Sheets-Sheet 1 Filed Nov. 23, 1964 N wE lnvenlor WWW B W E J w K .m R E Aug- 29, 1967 F. w. JEFFERIES LAMP CAPPING MACHINE Filed Nov. 23, 1964 3 Sheets-Sheet 2 Inventor FREDERICK w; J'EFFER A tlorneys I5 Sheets-Sheet 5 Filed Nov. 25, 1964 FIGS.

Inventor FRE'DERI'CK \V. JFFFERI ES A Horne y United States Patent 3,337,934 LAMP CAPPING MACHINE Frederick William Jelferies, Gillingham, Kent, England,

assignor to Bader Machinery Company Limited, Waybridge, England, a corporation of Great Britain Filed Nov. 23, 1964, Ser. No. 413,154 Claims. (Cl. 29-25.19)

This invention relates to machines for capping electric lamps, i.e., to the application of end caps to lamp bulbs after sealing thereof. The invention is applicable in the manufacture of lamps for general lighting purposes, including both bayonet cap lamps and Edison screw-cap lamps, and the invention will be more particularly described in that connection. However it is to be understood that the invention can be applied to machines for applying caps to other lamps, e.g., to so called pigmy lamps and to miniature bulbs for battery lamps, whether of a kind in which 'both lamp electrodes are threaded through the lamp cap or of a kind in which only one electrode is so threaded.

Methods of automatically threading caps over lamp electrodes have been proposed in which use is made of one or a pair of slender hollow or hollow-ended guide rods which pass through the hole or holes in the lamp cap and over the ends of the electrode or electrodes to be threaded whereupon the cap can be displaced along the guide rod or rods and up to the bulb.

In a capping machine using a guide tube or tubes the preliminary operation of threading the guide rod or rods has to be nicely controlled. In the known machine designed for threading bayonet caps, the caps loaded into holders on the threading machine are moved to a positioning device which ensures that the bayonet pins have a predetermined orientation relative to the cap holders before the guide tubes are moved to penetrate the cap holes. This method is satisfactory but interruption of working may occur in the event of a cap being present which has become so deformed that turning of the cap to bring its pins to predetermined angular positions does not serve to bring the holes in the cap to the positions which they should occupy to allow passage of the guide tubes. In that case the guide tubes may abut the cap and become bent.

The vitreous material lining a lamp cap provides a chamfered lead-in to the hole or holes at the base of the cap and the present invention is based on the idea of using the internal chamfering in the orientation of a cap by means of one or a pair of probes passing into the cap prior to the passage of a guide rod or rods through the cap. A single probe or a pair of probes is required depending on whether the lamps are Edison-screw or bayonet cap lamps. Hereafter reference will more particularly be made to bayonet cap lamps since the more important application of the invention is to the manufacture of lamps of this type.

By the movement of probes into a bayonet cap after it has been pre-on'entated through the agency of its bayonet pins it can be ensured that the cap holes are aligned with guide rods. If the holes have not been brought into the correct positions by the pre-orientation, the probes during their movement will eccentrically abut the internal chamferings and will thereby cam the cap angularly into its required position. By the movement of a .probe into an Edison screw-cap it can be ensured by cooperation of the probe with the internal chamfering that the cap hole is properly centered with respect to the guide rod.

i The present invention includes any machine for thread ing bayonet or other caps onto lamp electrodes in the manufacture of electric lamps having electrodes, compris- "ice ing bulb and cap holders, means for bringing a held cap into a predetermined orientation about its axis ready for threading of the cap by relative approach of the cap and bulb, including probes movable into the cap so that such probes correct any inaccuracy in the orientation of the cap by eccentrically abutting the internal chamferings leading to the holes for the electrodes, and hollow or hollow-ended guide rods for passing through the cap holes and over the extremities of the electrodes preparatory to said relative approach of the cap and bulb, means being provided for relatively axially displacing said guide rods and cap to cause said rods to pass through the cap holes following the operation of said probes. The invention also includes any similar machine suitable for capping Edison screw-cap or other lamps having a single thread electrode, the machine in this case using only one probe in the positioning of each cap. The possibility of this modification should be borne in mind in the following more detailed description of the invention directed specifically to bayonet cap lamps.

The probes may pass through the cap holes from the inside of the cap but their ends are preferably of a crosssectional size larger than the holes so that these ends seat into the conical chamferings. Probes having domed ends are preferred.

According to a further feature of the invention which may not be essential in all cases but which is thought to be of importance, the passage of the guide rods through the holes in the cap is guided by needles which pass through the cap holes from the inside of the cap and into the hollow ends of the guide rods, and the needles remain in the ends of the guide rods during the entry of these rods into the cap holes.

If the probes are arranged to penetrate through the cap holes and if the probes operate at a station where the guide rods operate, the probes may be formed at their ends as needles which enter the hollow ends of the guide rods. Preferably however the probes are hollow members within which separate needles are movable so as to advance through the cap holes and into the guide rods after the probes have seated in internal chamferings of the cap.

As an additional insurance against failure in operation of the machine tapering needle guides may be provided for accurately guiding the needles into the guide rods. Such needle guides must be formed so that they can be removed after the needles have entered the guide rods so as to permit the required relative motion between the guide rods and cap to cause the guide rods to pass through the cap holes. This threading of the guide rods through the cap holes is preferably achieved by movement of the cap while the guide rods remain stationary.

A capping machine according to the invention preferably comprises an indexing turret with pairs of guide rods at positions spaced angularly therearound so that caps can as it were successively be impaled on the successive pairs of guide rods at an appropriate station as the turret is indexed, and a bulb-carrying turret which is synchronised and spatially related to the guide rod turret so that the successive bulb carriers and pairs of guide rods are respectively brought to a station common to the two turrets where the capping of the bulbs takes place. The machine will at this station include means for locating the bulb electrodes preparatory to the movement of the guide rods over the electrode ends and the subsequent approach of the bulb and cap.

Preparatory to their movement onto the guide rod turret the caps are preferably loaded onto spaced cap holders on an indexing carrier which indexes in timed relation to the guide rod turret and is spatially related thereto so that the successive caps and pairs of guide rods are respectively brought in sequence to a common station where the caps are impaled on the guide rods. The cap carrier may move the caps, on their way to the said impaling station, to stations at which the caps are orientated to bring their holes into correct positions and to a station in which the holes are drilled through to remove any obstructing material.

In order that the invention may be fully understood an embodiment of capping machine in accordance therewith will now be described by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic plan view of the capping machine;

FIGS. 2a, 2b, 2c and 2d are detail views showing successive stages in the operation of impaling the caps on the guide rods; and,

FIG. 3 is a cross-sectional elevation of the guide rod turret and the electrode locating mechanism at the capping station.

Referring to FIG. 1, the machine comprises a rotary bulb-supporting turret A. The turret has six holding positions spaced at equal angular distances around the vertical axis of the turret and the turret is indexed to move the bulbs one by one successively from the Loading Station designated B at which the bulbs are loaded one by one onto the turret, to Station E at which the electrodes are cut to predetermined length and straightened at their ends and Station F where the electrodes are held located for the threading of the cap. The bulbs, after capping are moved by turret A to a take-off station G where the capped bulbs are removed for passing to a soldering machine where the electrodes are soldered to the caps in conventional manner. The loading of the bulbs onto turret A at Station B is etfectedby a transfer mech anism TM which may, e.g. comprise an oscillatable arm which grips the bulbs by suction and transfers them one by one in succession from a conveyor (not shown) to the turret A.

The electrode cutting and straightening mechanism at Station E and the electrode locating mechanism at Station F form no part of the present invention and require no further description herein.

Suflice it to say that the cutting mechanism comprises a pair of V-notched plates 1 which close in overlapped relation when a bulb has arrived at the station and grip the electrodes between the apices of the V-notches. The mechanism also includes a pair of cutters 2 which move into overlapped relation to cut the electrodes by a shear ing action just below the position at which they are gripped by the plates 1. After cutting the electrodes the cutters 2 move apart and while the plates 1 remain in their closed positions they are lowered so that the plates slide along the end portions of the cut electrodes and off the lower extremities thereof thereby ensuring that there are no deformities in the Wire ends. Finally the plates 1 swing apart and rise to their initial positions, allowing the turret A to move the bulb to Station F and bring a new bulb to Station E.

The caps are fed to a cap carrier H which has twentytwo pairs of cap-holding jaws spaced at equal distances around the endless course of the carrier. The caps are loaded onto the carrier at Station C, being fed thereto by a chute C. The carrier has jaws (not shown) for holding the caps but these form no part of the present invention and any conventional means may be employed for holding the caps on the carrier and releasing them at the Station E.

The carrier H is indexed to bring the caps one by one first to a Station K where the caps are pre-orientated in this case by means co-operating with the bayonet pins of the cap after each indexing motion of the carrier to bring the cap hole centres accurately or approximately into a predetermined vertical plane and then to a Station L where the position of the cap holes is checked and if necessary corrected and where the holes are cleared by a drilling mechanism. The Station L may comprise a pair of locating probes which are movable into the caps and operate to correct any inaccuracy in the hole positions by co-operating with the internal charnferings in the same way as the probes which are used at. Station M as will presently be described. The probes at StationL may be hollow and may remain within the cap while drills are passed upwardly through the holes in the cap and into the probe bores.

Alongside the turret A and cap carrier H is a turret I which is indexed in timed relation to the said turret A and the said carrier. As will presently be described in detail the turret J carries eight pairs of guide rods spaced at equal angular distances around the turret. The turrets A and I and the cap carrier H are spatially related so that during each dwell period a cap on carrier H and a pair of guide rods on turret J are situate at a common station M and another pair of guide rods on turret J and a bulb on turret A are situate at a common station F which is the Capping Station. On arriving at Station M, each cap is impaled on the pair of guide rods at that Station so that this pair of rods subsequently travels towards the Capping Station F with a cap already threaded onto the guide rods. When each pair of guide rods reaches Station F the rods are merely moved upwardly sufliciently to pass the guide rod ends over the ends of the electrodes of the bulb at that Station whereupon the cap is displaced along the rods and onto the bulb.

The operation of impaling the caps on the guide rods at Station M will now be described with reference to FIGS. 2 and 3.

Each of the FIGS. 2a to 2d inclusive illustrates one of the pairs of guide rods on the turret J. The guide rods 3 are supported in a bracket 4. It will be observed by reference to FIG. 3 that the bracket 4 forms part of a slide 5 which is vertically slidable in a guide way 6 on a tubular support 7. This support in turn encircles machine standard 8 and is rotatable therearound through the agency of a toothed crown wheel 9 secured to the. inside of the support 7 and a meshing pinion (not shown). The slide 5 has a rearwardly extending roller 10 which engages in an upwardly spiralling groove 11 in an upper part of the standard 8. Each pair of guide rods of turret J is supported in a bracket and engaged with the standard groove 11 in the same manner and as the. pairs of rods are indexed from Station M to Station F this groove causes the brackets 4 with their guide rods to rise to a higher level.

At Station M, above the level at which the caps are conveyed by the carrier H, is a pair of probes 12. carried by a supporting and operating head (not shown). On the simultaneous arrival of a cap and a pair of guide rods 3 at the Station M the probes are caused to move downwardly into the cap while it remains held by carrier H. The lower ends of the probes are domed and these domed ends seat into the internalchamferings in the vitreous lining of the cap as shown in FIG. 2b. Should the cap holes be slightly out of position the probes will encounter the chamferings eccentrically and turn the cap so that the hole positions-are corrected. Also located at Station M is a pair of arms 13 with upper and lower portions formed with facing peripheral recesses which register to form guideways when the arms are closed, and an upper member 14. The arms 13 close simultaneously with the downward movement of the probes so as to assume the position illustrated in FIG. 2b, in which the lower arm portions close about the guide rods 3 to hold these against lateral displacement and the upper arm portions lie immediately beneath the cap. At the same time the upper member 14 lowers on to the top of the cap so that this will be held between this member and the upper portions of arms 13 when the cap is subsequently released by carrier H. The upper portions'of arms 13 form downwardly convergent guide passages 15. After the lowering of the probes a pair of needles 16 which are located within the bores of the probes and have very fine end portions 17 are advanced through the holes in the cap and the convergent passage 15 of the arms 13 into the upper ends of the guide rods 3. It will now be seen that the guide rod holding portions of arms 13 and the convergent passages 15 formed -by the upper portions of these arms contribute in ensuring accurate registration of the needle points with the ends of the guide rods 3. In the next stage of the cycle of the mechanism at Station M the appertaining cap-holding jaws on carrier M open and release the cap and the arms 13 move slightly apart and these arms together with the probes and the upper member 14 move downwardly into the positions shown in FIG. 20. The cap is carried downwardly between the arms 13 and the upper member 14 and the downward movement is sufiicient to move the cap holes over the guide rods 3. The purpose of the slight opening movement of the arms 13 is to move the arms away from the guide rods 3 and needles 17 so that these do not obstruct the downward movement by their engagement by the arms but the opening movement of the arms .is not suflicient to cause the arms to cease supporting the cap. The needles do not take part in the downward motion referred to but remain in the same position within the ends of the guide rods. Finally the arms 13 move further apart so as to release the cap and the cap is carried down to the base of the guide rods by further downward motion of upper member 14, (FIG. 2d). The probes and needles now return to their original positions and the ,mechanism is ready for a further cycle of operations for impaling the next arriving cap on the next pair of guide rods.

When a pair of guide rods with a cap impaled thereon reaches Station F the guide rods have been raised by the spiralling groove 11 to the position shown on the right hand side of FIG. 3. At this Station the operation is as follows: A pair of electrode-gripping arms 18 carrying co-operating V-notched plates 19 move together to grip the electrode of the bulb which has arrived at this station; The electrodes are gripped adjacent their ends so that only the straightened portions at the electrode extremities 'are exposed. The length of the exposed portions is about 1 The plates 19 are shaped so that when closed they co-operate to define passages therethrough comprising a short cylindrical portion 20 within which the exposed electrode ends are accommodated, and tapering lead-in portions 21. The diameter of the cylindrical portions 20 is just in excess of the outer diameter of the guide rods 3. The mechanism for moving the electrode gripping arms may be of the conventional construction and further details need not here be given, except to say that as shown in FIG. 3 one of a pairof meshing pinions 22 which are mounted on a pair of vertical spindles 23 which carry the arms 18. The approach and recession motions of the arms are effected by oscillating the spindles through a linkage 24 driven as from the main machine drive of conventional construction.

Once the electrodes have been gripped, the bracket 4 with the pair of guide rods 3 is raised by a cam through the agency of a rod 25. This rod is secured at its upper end to a sector of the upper portion of the machine standard 8 which is vertically displaceable with respect to the other part of the standard. The upward movement of the rod 25 therefore lifts this sector (with the appertaining portion of groove 11 which is formed therein) and the bracket 4 as a unit. It should here be explained that the guide rods 3 while supported in the bracket 4 are not connected therewith but extend downwardly into a carrying plate 26 which is axially displaceable against a spring (not shown) within a lower portion 4a of the slide 5. During the aforesaid upward movement of rod 25 a lug 27 on the plate 26 abuts a stop screw 28 which is threaded through a lug fixed to the tubular support 7. At this point in the upward movement of rod 25 the upward movement of the plate 26 and the guide rods 3 is arrested. The screw 28 is set so that this arrest occurs when the upper ends of the guide rods 3 have moved along the convergent portions 21 of the passages formed by the electrode gripping plates 19 and into the cylindrical portions 20 of these passages so that the upper ends of the guide rods are over the electrode extremities. The upward movement of rod 25 continues beyond this point sufiiciently to cause the bracket 4 which is supporting the lamp cap to move this cap upwardly along the guide rods 3 and onto the lamp bulb, the arms 18 being moved apart during or just prior to this continued upward movement of the lamp cap.

Before the rod 25 is again lowered to its original position the lamp cap must be supported against the bulb to give an opportunity for the paste to set. This support of the lamp cap in its raised position is achieved by cap supporting jaws (not shown) mounted on a turret underlying and co-axial with the bulb-supporting turret. Such an arrangement of cap supporting jaws for supporting the lamp caps after threading may have six pairs of cap supporting jaws carried at an appropriate level beneath turret A, one pair of jaws beneath each pair of bulbholding jaws and each pair of jaws may be closed during the dwell at Station F at a moment following the lifting of the cap onto the bulb by the bracket 4. The jaws remain closed during the subsequent lowering of the bracket and while the turret A and the cap supporting jaws are indexed to bring the capped bulb to the take-01f Station G, where the capped bulbs are removed for passing to the soldering machine.

As hole-locating probes are used at Station L it may be possible'to dispense with the use of such probes at Station M in which case this Station may merely comprise means for lowering the orientated cap onto the guide rods or if desired it may also com-prise needles which pass downwardly through the cap holes into the guide rod ends. It is preferable however also to use probes at Station M as this safeguards against any risk of the caps becoming displaced in their holders during movement from Station L to Station M. Moreover, the design of the Station M mechanism as described above so that the probes accompany the downward-motion of the cap until the guide rods have entered the cap holes ensures a very positive control of the cap movement.

I claim:

1. A machine for threading caps having electrode receiving holes with internal chamferings onto lamp electrodes in the manufacture of electric lamps, comprising bulb and cap holders, means for bringing a held cap into a predetermined orientation about its axis ready for threading of the cap by relative approach of the cap and bulb and including at least one probe movable into the interior of the cap from its wide chamfered end so that each probe corrects any inaccuracy in the orientation of the cap by eccentrically abutting the internal chamferings leading to a hole for the electrode, at least one hollow-ended guide rod in axial alignment with said probe and separate therefrom for passing through a cap hole and over the extremity of the electrode preparatory to said relative approach of the cap and bulb, and means for relatively axially displacing said guide rod and cap to cause said rod to pass through the cap hole from the opposite direction following the operation of said probe.

2. A machine for threading Edison-screw or other single contact caps having electrode receiving holes with internal chamferings onto lamp electrodes in the manufacture of electric lamps, comprising bulb and cap holders, means for centering a held cap ready for threading of the cap by relative approach of the cap and bulb and including a probe movable into the cap from its wide chamfered end so that such probe corrects any inaccuracy in the positioning of the cap by eccentrically abutting the internal chamfering leading to the hole for the electrode, a hollow-ended guide rod separate from said probe for passing through the cap hole and over the extremity of the electrode preparatory to said relative approach of the cap and bulb, and means for relatively axially displacing said guide rod and cap to cause said rod to pass through the cap hole from the opposite direction following the operation of said probe.

3. A machine according to claim 1 wherein each probe end is of a size and shape such that it can seat into the internal chamfering surrounding the cap hole.

4. A machine for threading caps having electrode receiving holes with internal chamferings onto lamp electrodes in the manufacture of electric lamps, comprising bulb and cap holders, means for bringing a held cap into a predetermined orientation about its axis ready for threading of the cap by relative approach of the cap and bulb and including at least one probe movable into the interior oftthe .cap so that said probe corrects any inaccuracy in the orientation of the cap eccentrically abutting the internal chamferings leading to a hole for the electrode, and at least one hollow-ended guide rod for passing through a cap hole and over the extremity of the electrode preparatory to said relative approach of the cap and bulb, means for relatively axially displacing said guide rod and cap to cause said rod to pass through the cap hole following the operation of said probe, and a needle for co-operating with each guide rod which needle in operation passes through a said lamp cap hole from the inside of the cap and enters the hollow end of said rod and remains in such rod end during entry of this rod into the cap hole.

5. A machine according to claim 4 wherein said needle is movable within a bore in said probe and advances from the probe end after the latter has seated in said internal chamfering.

6. A machine according to claim 4 comprising means forming a tapering guide passage between said capand guide rod for guiding the needle into such rod.

7. A machine for threading caps having electrode receiving holes with internal chamferings onto lamp electrodes in the manufacture of electric lamps, comprising bulb and cap holders, means for bringing a held cap into a predetermined orientation about its axis ready for threading of the cap by relative approach of the cap and bulb and including at least one probe movable into the interior of the cap from its Wide chamfered end so that each probe corrects any inaccuracy in the orientation of the cap by eccentrically abutting the internal chamferings leading to a hole for the electrode, at least one hollowended guide rod in axial alignment with said probe and separate therefrom for passing through a cap hole and over the extremity of the electrode preparatory to said relative approach of the cap and bulb, and means for relatively axially displacing said guide rod and cap to cause said rod to pass through the cap hole from the opposite direction following the operation oftsaid probe, said latter means being operative to move said cap over the guide rod while said rod remains stationary.

8. A machine for threading caps having electrode receiving holes with internal chamferings onto lamp electrodes in the manufacture of electric lamps, comprising a turret with a plurality of guide rods, a cap carrier, means for indexing said cap carrier and said turret synchronously so that caps loaded on said carrier are brought one by one successively to a station common to said turret and carrier at which the cap is above at least one of said guide rods on the turret, means operative oncompletion of each indexing motion to cause the cap at that station to become impaled on the respective guide rod, a bulb holder operable to present a bulb to'the cap, at

least one probe movable into the interior of the cap from its wide chamfered end so that each probe corrects any inaccuracy in the orientation of the cap by eccentrically abutting the internal chamferings leading to a hole for the electrode, said respective guide rod having a hollow end and being adapted to pass through a cap hole and over the extremity of the electrode preparatory to said relative approach of the cap and bulb, means for relatively axially displacing said guide rod and cap to cause said rod to pass through the cap hole following the operation of said probe and from the opposite direction, and a needle for cooperating with said guide rod which needle in operation passes through the lamp cap hole from the inside of the cap and enters the. hollow end of said rod and remains in such rod end during the entry of said rod into the cap hole. I

9. A machine according to claim 8 wherein each said probe for correcting any inaccuracy in the position of a cap with respect to each guide rod to be passed therethrough operates at said station common to the turret and carrier. r

10. A machine according to claim 8, suitable for threading bayonet caps, comprising means operative upon completion of each indexing motion of said cap carrier and co-operative with the bayonet pins'of a cap on its way to said station to bring such cap into a position in which said pins are in a substantially predetermined vertical plane.

References Cited UNITED STATES PATENTS 3,046,635 7/1962 Terez 29-2519 WILLIAM I. BROOKS, Primary Examiner.

JOHN F. CAMPBELL, Examiner. 

8. A MACHINE FOR THREADING CAPS HAVING ELECTRODE RECEIVING HOLES WITH INTERNAL CHAMFERINGS ONTO LAMP ELECTRODES IN THE MANUFACTURE OF ELECTRIC LAMPS, COMPRISING A TURRET WITH A PLURALITY OF GUIDE RODS, A CAP CARRIER, MEANS FOR INDEXING SAID CAP CARRIER AND SAID TURRET SYNCHRONOUSLY SO THAT CAPS LOADED ON SAID CARRIER ARE BROUGHT ONE BY ONE SUCCESSIVELY TO A STATION COMMON TO SAID TURRET AND CARRIER AT WHICH THE CAP IS ABOVE AT LEAST ONE OF SAID GUIDE RODS ON THE TURRET, MEANS OPERATIVE ON COMPLETION OF EACH INDEXING MOTION TO CAUSE THE CAP AT THAT STATION TO BECOME IMPALED ON THE RESEPECTIVE GUIDE ROD, A BULB HOLDER OPERABLE TO PRESENT A BULB TO THE CAP, AT LEAST ONE PROBE MOVABLE INTO THE INTERIOR OF THE CAP FROM ITS WIDE CHAMFERED END SO THAT EACH PROBE CORRECTS ANY INACCURACY IN THE ORIENTATION OF THE CAP BY ECCENTRICALLY ABUTTING THE INTERNAL CHAMFERINGS LEADING TO A HOLE FOR 